The fixation of dust with the formation of visual effects of dust is a widespread problem with plastic mouldings. In this context see, for example, Saechtling, Kunststoff-Taschenbuch, 26th edition, Hanser Verlag, 1995, Munich, p. 140 et seq. Dust deposits are a particular nuisance in transparent mouldings where they compromise function. Such mouldings are used, for example, for the optical data storage sector, in electrical engineering and automotive construction, in the building construction sector, for containers for liquids or for other optical applications. The fixation of dust is undesirable in all these applications and may impair function.
A known method of reducing the fixation of dust on plastic bodies is the use of antistatic agents. The literature describes antistatic agents for thermoplastics (see, for example, Gächter, Müller, Plastic Additives, Hanser Verlag, Munich, 1996, p. 749 et seq.), which limit the fixation of dust. These antistatic agents improve the electrical conductivity of the plastic moulding compositions and in this manner dissipate surface charges which form during manufacture and use. Dust particles are consequently attracted to a lesser extent, and the fixation of dust is hence reduced.
A distinction is generally made between internal and external antistatic agents. An external antistatic agent is applied to the plastic moulding after processing, an internal antistatic agent is added to the plastic moulding compositions as an additive. The use of internal antistatic agents is generally desirable for economic reasons, since no additional working steps are necessary for applying an antistatic agent after processing.
Those internal antistatic agents for thermoplastics which have been described hitherto in the literature generally have one or more of the following disadvantages:                breakdown of molecular weight of the thermoplastic        effectiveness only at high concentrations (>0.5%)        turbidity in transparent thermoplastics        insufficient effect to enable electrostatic discharge to take place, for example after injection moulding, and thus to avoid the fixation of dust        discoloration.        
Sulfonic acid salts are a class of antistatic agents frequently described for use in thermoplastics. For example JP-06228420 A 940816 describes aliphatic sulfonic acid ammonium salts in polycarbonate as an antistatic agent. However, these compounds lead to breakdown of molecular weight.
Quaternary ammonium salts of perfluoroalkylsulfonic acids are known, likewise the use thereof in thermoplastics, as in DE 2 506 726, for example. The latter application describes quaternary ammonium salts of perfluoroalkylsulfonic acids as mould release agents for polycarbonate. The examples described in that application, however, lead in polycarbonate to marked yellowing during processing, which is undesirable in particular for transparent and white-coloured formulations.